When a purchase is made, whether of a piece of furniture or clothing or simply a pen, a contract is concluded between the customer and the merchant. The terms of the contract are found on the bill or sales slip that is given to the customer.
Apart from exceptions, the law does not provide for the cancellation of a purchase if the item is not defective but the customer simply doesn't think it's needed anymore or dislikes the colour. In such instances, the customer has no choice but to amicably negotiate cancellation of the purchase with the merchant.